Medical delivery system comprising locking ring with l-shaped grooves

ABSTRACT

A medical delivery system comprising a container which is adapted to be fastened to a dosing assembly. One of the container and the dosing assembly comprises a rotatable element adapted to cooperate with the other one of the container and the dosing assembly, so as to lock/fasten the container to the dosing assembly. Furthermore, the present invention relates to a container and a dosing assembly for use in the medical delivery system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. application Ser. No.12/447,757, filed Apr. 1, 2010, which is a 35 U.S.C. §371 national stageapplication of International Patent Application PCT/EP2007/062661(published as WO 2008/062025), filed Nov. 21, 2007, which claimedpriority of European Patent Application 06024098.3, filed Nov. 21, 2006;this application further claims priority under 35 U.S.C. §119 of U.S.Provisional Application 60/873,079, filed Dec. 6, 2006, incorporatedherein by reference.

FIELD OF THE INVENTION

The present invention relates to a medical delivery system comprising acontainer which is adapted to be fastened to a dosing assembly. Inparticular the present invention relates to a medical delivery systemwherein one of the container and the dosing assembly comprises arotatable element adapted to cooperate with the other one of thecontainer and the dosing assembly. Furthermore, the present inventionrelates to a container and a dosing assembly for use in the medicaldelivery system.

BACKGROUND OF THE INVENTION

Generally, in order to provide superior medication delivery deviceswhich are likely to be well received by particular groups of patients, agreater diversity in drug delivery systems have been launched to thebenefit of patients. As the number of commercially available deliverysystems increase, numerous different types of medication holdingcartridges or containers are distributed. Most of these types ofcontainers differ in various aspects.

Each medicament container may be filled with a particular type ofmedicament selected from a large variety of different medicaments, butalso different kinds of the same class of medicament (e.g. rapid or longacting insulin) and different concentrations of each particularmedicament may be accommodated in the containers.

Moreover, different container volumes may be introduced in order tocustomize each container, and, thus, the delivery system to the needs ofparticular users. Variation of container volume may be provided bychanging the length or diameter of the container. These modificationsusually imply corresponding modifications of the dosing assembly of amedication delivery system, so as to provide a particular stroke of adriving element for expelling the medicament from the container or toprovide optimal dosing precision. Further discrimination betweendifferent medicament containers may be occasioned by the designrequirements for each particular delivery system, such as requiredsliding friction of the piston accommodated in the container.

In order to discriminate between a larger variety of availablecontainers, numerous container coding and coupling systems have beendeveloped. The following mechanical coding and coupling systems areknown in the art:

U.S. Pat. No. 5,611,783 relates to a pen shaped syringe comprising adistal part which may comprise an ampoule and a proximal part containinga dose setting and drive mechanism. The proximal and distal parts haveinterlocking bayonet coupling means. Protrusions may be provided to forma pattern ensuring that a certain distal part may only be used inconnection with a certain proximal part.

WO 03/017915 A1 discloses a cartridge having a distal end provided witha mechanical coding. The mechanical coding has the form of a circularprotrusion where the circular outer diameter is dedicated a specificconcentration of insulin contained in the cartridge.

U.S. Pat. No. 5,693,027 discloses a plastic top for adapting a standardcartridge to a chosen syringe. The plastic top may be provided withmeans for keyed engagement with corresponding means in a syringe to keepit unrotable when mounted with a cartridge in the syringe. In some typesof syringes such keyed engagement between cartridge and syringe isfurther used to ensure that only a certain type of cartridge is used.

U.S. Pat. No. 6,648,859 B2 discloses a drug cartridge assembly for usewith a reuseable pen body assembly of a medication delivery pen. Inorder to eliminate cross-use the pen body assembly and the drugcartridge are keyed i.e. they may be threadedly engaged by correspondingthreads and grooves, bayonet threads, and grooves, snap fits or a pairof lugs that mate in reverse Luer-Lock manner. The mating members areselected so as to prevent cross-use with other assemblies, e.g., thepitch of the threads may be angled so as to mate only with one anotherand not with other assemblies.

Yet another prior art system is described in DE 201 10 690.

GB patent No. 301,961 discloses a syringe wherein a barrel memberholding an ampule is provided with a radially extending pin which iscooperating with a bayonet slot formed in a head. The head is attachedto the barrel by a conventional bayonet coupling movement including arelative rotational movement between barrel and head.

It is an object of a preferred embodiment of the present invention toprovide an alternative to the known systems. Furthermore, it is anobject of a preferred embodiment of the present invention to provide amedication delivery system with a large number of possible codinggeometries, while obtaining a robust coding system.

Furthermore, it is an object of a preferred embodiment of the presentinvention to provide a coding system wherein the user experiencessubstantially the same operational fastening/coupling/locking movementwhen the container and dosing assembly of a predetermined medicaldelivery system are coupled/uncoupled (locked/unlocked) to each otherregardless of the specific choice among sets of compatiblecontainer/dosing assemblies.

Furthermore, it is an object of a preferred embodiment of the presentinvention to provide an intuitive and simple fastening mechanism forfastening the container to the dosing assembly.

Moreover, it is an object of the present invention to provide alocking/fastening system wherein the user experiences an auditive ortactile feed back when locking the container to the dosing assembly.

SUMMARY OF THE INVENTION

In a FIRST aspect the present invention relates to a medical deliverysystem comprising:

-   -   a container adapted to contain a medicament in a chamber defined        by the container and a slidably arranged piston which is        moveable in a distal direction towards an outlet so as to reduce        the volume of the chamber and expel the medicament through the        outlet;    -   a dosing assembly adapted to be fastened to the container, so as        to allow a driver of the dosing assembly to move the piston of        the container in the distal direction;        wherein one of the dosing assembly and the container defines a        first part comprising a fixed part and a rotatable element        defining one or more projection(s) and/or groove(s) which during        fastening of the container to the dosing assembly is/are adapted        to be received in/by one or more corresponding groove(s) and/or        projection(s) of a second part which is defined by the other one        of the dosing assembly and the container, so as to fasten the        container to the dosing assembly; and        wherein the rotatable element is adapted to rotate about a        longitudinal axis of and relative to the container and/or the        dosing assembly during fastening of the container to the dosing        assembly.

The container and the dosing assembly may be locked rotationally to eachother during fastening of the container to the dosing assembly. In oneembodiment, only a part of the container and only a part of the dosingassembly are locked rotationally relative to each other during fasteningof the container to the dosing assembly. In another embodiment the firstpart except from the rotatable element and the second part are lockedrelative to each other during fastening of the container to the dosingassembly. The rotational lock may be achieved by providing a grove andtongue arrangement on the two parts to be locked rotationally.Alternatively, or as a supplement the two parts may each have across-section preventing relative rotation, e.g. the container may havean elliptical cross-section and the dosing assembly may define acorresponding elliptical cavity for receiving the container. Byproviding the rotational lock, fastening of the container to the dosingassembly is easy and intuitive for the user, as the container isfastened to the dosing assembly through a pure or substantially puretranslational movement.

By varying the rotational distribution and/or geometrical dimensions ofthe projections/grooves formed in the rotatable element and thecorresponding part of the other of the dosing assembly/container notholding the rotatable element in different medical delivery systemsaccording to the present invention, it may be ensured that a containerof a first medical delivery system is coded such that it cannot befastened to a dosing assembly of a second medical delivery system.Analogously, it may be ensured that the container of the second medicaldelivery system is coded such that it cannot be fastened to the dosingassembly of the first medical delivery system. Accordingly, the medicalsystem according to the present invention improves user safety as onlypredetermined containers may be attached to a specific dosing assembly.Thus, the dosing assembly may be designated to be used with apredetermined kind and/or concentration of a medicament and containersaccommodating other concentrations or types of medicaments cannot beattached to the dosing assembly. Furthermore, by ensuring that thecontainer and the dosing assembly (with the exception of the rotationalelement) is locked rotationally to each other during fastening of thecontainer to the dosing assembly, it is ensured that a large number ofdistinct codings can be obtained.

In the context of the present invention the term “medical deliverysystem” shall be understood as any system capable of administering amedicament-containing flowable drug. Examples of medical deliverysystems are infusion pump applications, dosers, pen-shaped dosers,motor-dosers, and automated syringes such as the AutoPen™.

The invention is applicable to all kinds of medicament delivery devicescapable of delivering a medicament to a user from a container which isadapted to be coupled to a dosing assembly of the delivery device. Thedelivery device may include any delivery device for transcutaneous,subcutaneous, intravenous, intra muscular or pulmonary administration ofa drug.

As used herein, the term “medicament” is meant to encompass anymedicament-containing flowable drug capable of being passed through adelivery means such as a hollow needle in a controlled manner, such as aliquid, solution, gel or fine suspension. Representative medicamentsincludes pharmaceuticals such as peptides, proteins (e.g. insulin,insulin analogues and C-peptide), and hormones, biologically derived oractive agents, hormonal and gene based agents, nutritional formulas andother substances in both solid (dispensed) or liquid form.

The chamber of the container may defined by one or more sidewalls of thecontainer and the slidably arranged piston. In most embodiments at leasta part of the container is ring-shaped (having a cylindricalcross-section) and defines a cylindrical cavity in which the piston isreceived. The distal end of the container may comprise a seal forpenetration by a cannula so as to allow a medicament contained in thechamber to be expelled through the cannula. The distal end of thecontainer may be adapted to be attached to a holder holding a cannula.As an example the distal end of the container may comprise a threadadapted to cooperate with a corresponding thread of the holder so as toallow the holder to be screwed onto the container.

The outlet of the container may be adapted to cooperate with or bedefined by a cannula or a needle or a needle hub or an infusion set, orany other fluid communicating conduit adapted to provide fluid access toa medicament accommodated in the container.

The driver of the dosing assembly may comprise a piston rod adapted tomove the piston in the distal direction. The piston rod may comprise anelement which is more rigid than the piston and is adapted to abut atleast a part of and preferably most of the proximal facing surface ofthe piston whereby a force applied by the piston rod to the rigidelement is applied to a larger area of the proximal surface of thepiston than if the piston rod had engaged the piston directly.

The rotatable element may be ring-shaped and may in use encircle atleast a part of the dosing assembly and/or the container. Alternatively,the rotatable element may encircle only a part of the container and/orthe container.

In the context of the present invention the term “remainder of the firstpart” shall designate the first part except from the rotatable element.In some embodiments, the remainder of the first part may form a housingstructure which is adapted to be gripped by the palm of the user. Inthat case, preferably, the rotatable element defines an exterior surfacewhich is comparatively smaller than the remainder of the first part.

In one embodiment the rotatable element defines one or more projections(such as two, three, four or five) each of which is adapted to engage acorresponding/mating/matching depression of the second part. In a secondembodiment the rotatable element defines one or more grooves (such astwo, three, four or five) each of which is adapted to engage acorresponding/mating/matching projection of the second part. In a thirdembodiment the rotatable element comprises one or more projections andone or more grooves. In the latter embodiment, the projection(s) of therotatable element is/are adapted to engage one or more grooves of thesecond part and the groove(s) is/are adapted to engage one or moreprojections of the second part.

In order to ensure that the container and the dosing assembly may belocked to each other translationally, the one or more projection(s)and/or groove(s) of the rotatable element may engage the one or moregroove(s) and/or projection(s) of the second part during fastening ofthe container to the dosing assembly. In one embodiment the containerand the dosing assembly are locked for relative translational movementin one direction when the projection(s) engage the grove(s), whereby thecontainer and the dosing assembly may be moved further towards eachother but not away from each other. In another embodiment the containerand the dosing assembly are locked for relative translational movementin both translational directions when the projection(s) engage thegroove(s) whereby they cannot be moved further towards or away from eachother.

Advancement of the projection(s) into the groove(s) during fastening ofthe container to the dosing assembly, may cause the rotatable element torotate about the longitudinal axis of and relative to the containerand/or the dosing assembly. In one embodiment this is achieved byproviding one or more projections on the container and a correspondingnumber of grooves on the rotatable element. In order to make therotatable element rotate during fastening of the container to the dosingassembly, at least a part of the groove may extent in a directiontransverse to the longitudinal direction of the device. Examples ofgrooves causing the rotatable element to rotate are L-shaped, V-shapedand S-shaped grooves.

In most embodiments wherein fastening of the container to the dosingassembly causes the rotatable element to rotate, the rotatable elementwill also rotate during defastening/decoupling/unlocking of thecontainer from the dosing assembly. Accordingly, locking of therotatable element rotationally relative to the remainder of the firstpart prevents unlocking of the container from the dosing assembly. Thedevice may in one embodiment comprise such a lock for locking therotatable element relative to the container and/or the dosing assembly.When a container is not fastened to the dosing assembly, activation ofthe lock prevents fastening of a container to the dosing assembly. When,as described above, a container is fastened to the dosing assembly,activation of the lock prevents defastening/decoupling/unlocking of thecontainer from the dosing assembly.

It will be appreciated that the shape of the groove(s) determines thedegree of rotation of the rotatable element. In one embodiment thegroove(s) is/are shaped such that the rotatable element during fasteningis rotated less than one revolution relative to the container and/or thedosing assembly, such as less than 180 degrees, such as less than 120degrees, such as less than 90 degrees, such as less than 60 degrees,such as less than 45 degrees, such as less than 30 degrees, such as lessthan 15 degrees.

Moreover, the groove(s) of the first and/or second part may be shapedsuch that advancement of the corresponding projection into the grooveduring fastening of the container to the dosing assembly, causes therotatable element to rotate in a first direction and subsequently in aopposite second direction relative to the first and/or second part. Whenadvanced in the first direction the rotatable element may be rotated Xdegrees, and when rotated in the second direction the rotatable elementmay be rotated Y degrees. The numerical value of X and Y may beidentical e.g. when X=30 degrees and Y=−30 degrees, whereby X+Y=0.Alternatively, X+Y may be different from zero, such as ±5 degrees, suchas ±10 degrees, such as ±15 degrees, such as ±20 degrees. When X+Y≠0,the rotational element is rotated more in one of the first and seconddirection than in the other one of the first and second direction. As anexample the rotatable element may be rotated 30 degrees in the firstdirection and subsequently 20 degrees in the second direction duringfastening of the container to the dosing assembly.

At least one of the grooves of the first and/or second part may define afirst and a second groove part. The first and second groove parts may beshaped such that advancement of a corresponding projection into saidgroove parts causes the rotatable element to rotate in the firstdirection when the projection, during fastening, is advanced in thefirst groove part and in the second direction when the projection,during fastening, is advanced in the second groove part. In oneembodiment at least one of the first and second groove parts issubstantially straight and the first and second groove parts areinterconnected by an interconnecting groove part. In one embodiment ageneral direction of the second groove part may extend in a directiontransverse to the axial direction of the medical delivery system and atan angle of larger than 70 degrees to said axial direction, such asabove 80 degrees.

In one embodiment the rotatable element may rotate freely relative tothe remainder of the first part and/or relative to the second part.However, in most embodiments the rotatable element is adapted to berotated between a first position and a second position relative to thecontainer and/or the dosing assembly (i.e. relative to the remainder ofthe first part and/or the second part). Moreover, the rotatable elementmay be biased towards the first position. In order to bias the rotatableelement towards the first position, the first part may comprise abiasing means arranged to bias the rotatable element towards the firstposition. The biasing means may comprise a torsion spring having a firstend fastened to the rotatable element and a second end fastened to theremainder of the first part. Alternatively, the biasing means maycomprise flat spring retained relative by the remainder of the firstpart and extending into a cavity of the rotatable element such thatrotation of the rotatable element causes the flat spring to be bendwhereby the rotational element is urged towards the first position. Itwill be appreciated, that the flat spring need not be flat as long at ithas a large axial extent relative to the thickness of the spring and aslong as it is bendable.

In one embodiment advancement of the projection in the first groove partduring fastening of the container to the dosing assembly, causes therotatable element to be rotated away from the first position. Moreover,advancement of said projection in the second groove part duringfastening of the container to the dosing assembly, may cause therotatable element to be rotated back towards the first position. Whenthe projection during fastening is advanced in the first groove part andthe rotatable element is forced away from the first position, potentialenergy may be stored/accumulated in/by the spring. Additionally,potential energy stored in the spring may be released/dispensed when theprojection during fastening is advanced in the second groove part.

In one embodiment the second groove part is steeper than the firstgroove part relative to the axial direction of the medical deliverysystem. In the context of the present invention the term “steeper” shallbe understood such that the steepness of a surface, plane etc. increasesthe closer the surface, plane etc is to define a right angle relative toreference such as an axial direction of the medical delivery system. Inone embodiment a plane extending in a general direction of the secondgroove part defines an angle relative to the axial direction of themedical delivery system which is above 70 degrees. It will beappreciated that a spring-biased rotational element with a steep secondgroove part e.g. above 70 degrees, must be rotated by a user in order toallow the container to disengage the dosing assembly. Moreover, it willbe appreciated that the steeper the second groove part is the harder itis for the container to disengage the dosing assembly by accident, asthe spring urges the projections towards the bottom of the secondgroove, whereby the projections cannot move from the second groove partto the first groove part.

In one embodiment the one or more of the projections and/or the groovesdefine predetermined coding geometries preventing the container frombeing fastened to the dosing assembly unless each of the grooves and theprojections define a predetermined coding geometry which may be selectedfrom a predetermined group of coding geometries. The coding geometry ofeach of the grooves and/or projections may be defined by at least oneof: a circumferential extent of the groove(s) and/or the projection(s),an axial extent of the groove(s) and/or the projection(s), a radialextent of the groove(s) and/or the projection(s) and the circumferentialposition of the groove(s) and/or the projection(s).

One embodiment comprises:

-   -   a first container according to any of the preceding claims        adapted to be fastened to a first dosing assembly according to        any of the preceding claims; and    -   a second container according to any of the preceding claims        adapted to be fastened to a second dosing assembly according to        any of the preceding claims; and        wherein at least one of the groove(s) and the projection(s) is        adapted to prevent the first dosing assembly and second        container from being fastened to each other, and to prevent the        second dosing assembly and the first container from being        fastened to each other.

In one embodiment the container comprises a cartridge holder which isadapted to accommodate a cartridge defining said chamber. The secondfastening means may be defined by or attached to the cartridge holder.Moreover, the groove(s)/projection(s) may be defined by the cartridgeholder. When the cartridge and the cartridge holder are two distinctelements, the cartridge may be frictionally retained in the cartridgeholder. In one embodiment the cartridge is made of glass and thecartridge holder is made of a non-glass material for protecting theglass cartridge. The cartridge may be non-removably retained in thecartridge holder, such that if the cartridge is removed from thecartridge holder it cannot be reattached by hand and without tools. Thisprovides the advantage that the cartridge holder cannot be reused whenthe cartridge has been emptied, accordingly a cartridge with a wrongmedicament cannot be inserted into the cartridge holder and be dispensedby use of the dosing assembly. The cartridge holder and the cartridgemay define a monolithic element, i.e. forming a one element withoutseams. Such a monolithic element may be formed as a molded article madeof a synthetic resin such as Topas® or polypropylene. Such a moldedarticle may include the fastening and coding geometries which are formedduring molding. However, any material which is suitable for long-termstorage of the specific medication to be accommodated in the containermay be used.

In a SECOND aspect the present invention relates to a container for usein a medical delivery system according to the first aspect of theinvention. The invention according to the second aspect may comprise anyfeature and/or element of the invention according to the first aspect.As an example the container may be adapted to contain a medicament in achamber defined by the container and a slidably arranged piston which ismovable in a distal direction towards an outlet so as to reduce thevolume of the chamber and expel the medicament. In one embodiment, thecontainer may comprise a rotatable element adapted to rotate about alongitudinal axis of and relative to the remainder of the container. Therotatable element define one or more projection(s) and/or groove(s). Theone or more projection(s) and/or groove(s) of the rotatable element maybe adapted to receive one or more corresponding groove(s) and/orprojection(s) of a dosing assembly, so as to fasten the container to thedosing assembly. The container may provide, on the remainder of thecontainer as defined above, one or more projections and/or groovesadapted to cooperate with mating projections or grooves formed in thedosing assembly, so as to provide a rotational lock between the dosingassembly and the remainder of the container. The rotational lock mayform an axially extending guide ensuring rotationally fixation of theremainder of the container with respect to the dosing assembly duringcomplete or part of the fastening procedure.

In a THIRD aspect the present invention relates to dosing assemblysuitable for use in a medical delivery system according to the firstaspect of the invention. The invention according to the third aspect maycomprise any feature and/or element of the invention according to thefirst aspect. Also, the invention according to the third aspect may beformed to cooperate with a container assembly according to the secondaspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 2 disclose a medical delivery system according to a firstembodiment,

FIG. 3 discloses a sectional view in the longitudinal direction of thesystem according to the first embodiment,

FIG. 4 discloses an exploded view of a system according to the firstembodiment, and

FIG. 5 discloses a medical delivery system according to a secondembodiment.

DETAILED DESCRIPTION OF THE DRAWINGS

FIGS. 1-4 disclose a medical delivery system 100 according to a firstembodiment. The system 100 comprises a container 102 and a dosingassembly 104, which for simplicity reasons, is not shown in itsentirety. However, it will be appreciated that the dosing assembly 104may also comprise a dose setting mechanism and an injection mechanism.Moreover, the system 100 comprises a rotatable element 106, which ismade of an outer part 108 visible in FIG. 1 and an inner part 110visible in FIG. 2. The inner part 110 and the outer part 108 may befastened to each other through a snap-lock, gluing or welding or by anyother means of fastening which causes rotation of the outer part 108 tobe transferred to the inner part 110 when the two parts are fastened toeach other. In an embodiment the inner and outer parts 110,108 define amonolithic element i.e. made in one piece without seams.

The rotatable element 106 is retained axially relative to the dosingassembly 104 due to snap locks 112, which engage a distal facing surface114 of the rotatable element 106. In the axially retained position therotatable element 106 may rotate relative to the dosing assembly 104between a first and a second position. In FIG. 2 the rotatable element106 is shown in the first position towards which the rotatable element106 is biased due to torsion spring 116. The torsion spring 116comprises a distal tap 118 and a proximal tap 120 visible in FIG. 4which engage indentations of the rotatable element 106 and the dosingassembly 104, respectively. Accordingly, rotation or the rotatableelement 106 in a first rotational direction 119 relative to the dosingassembly 104 causes the spring 116 to expand. When the rotatable element106 is positioned in the first position, the spring 116 is in a restposition whereas when the rotatable element 106 is in the secondposition the spring 116 is in a non-rest position wherein potentialenergy is stored in the spring 116, and the spring 116 urges therotatable element 106 towards the rest position of FIG. 2.

The rotatable element 106, the torsion spring 116 and the dosingassembly 104 define a first part 122 and the container 102 defines asecond part 124, see FIG. 4. The container 102 defines three projections126 each of which is adapted to engage corresponding L-shaped grooves128 of the rotatable element 106 during insertion of the container 102into the dosing assembly 104.

Moreover, the dosing assembly defines linear grooves 130 which theprojections 126 additionally engage during insertion of the container102 into the dosing assembly 104, whereby the container 102 isrotationally fixed relative to the dosing assembly 104.

Due to the rotational lock caused by the groove-tongue engagementbetween the projections 126 and the linear grooves 130, translationalmovement of the projections 126 towards the dosing assembly 104 causesthe rotatable element 106 to rotate as the projections 126 are advancedinto the L-shaped grooves 128. As the L-shaped grooves comprises a firstgroove part 132 and second groove part 134, the rotatable element willinitially rotate in the first rotational direction 119 when theprojections 126 are advanced translationally in the first groove part132 and subsequently in a direction opposite the first rotationaldirection 119, when the projections 126 are advanced translationally inthe second groove parts 134.

In FIG. 2 the second groove part 134 is steeper than the first groovepart 132, relative to the axial direction of the device. In the presentcontext, the term “steeper” shall be understood such that the steepnessof a surface, plane etc. increases the closer the surface, plane etc isto define a right angle relative to reference in this case the axialdirection of the medical delivery system. It will be appreciated thatthe steeper the groove parts 132,134 are, the larger the angularrotation of the rotatable element will be, when the projections aremoved a predetermined axial distance relative to the rotatable element106 and/or the dosing assembly 104.

In a special embodiment the second groove part 134 is substantially atright angle relative to the axial direction of the device, and thusadvancement of the projection 126 from the first groove part 132 intothe second groove part 134 causes the rotatable element to be movedrapidly into the first position due to the torsion spring 116. When therapid movement is terminated due to a bottom surface 136 (see FIG. 4) ofthe second groove part 134 being forced towards a surface of theprojection 126 (as shown in FIG. 2), the user is provided withaudio/tactile information indicating that the container 102 is properlyfastened to the dosing assembly 104.

Moreover it will be appreciated that the steeper the second groove part134 is, the better the container 102 is secured to the dosing assembly104. As the rotatable element is forced towards the first position asdisclosed in FIG. 2, the user must rotate the rotatable element awayfrom the first position (against the force of the spring 116) in orderto allow the projections to be moved from the second groove part 134into the first groove part 132.

FIG. 3 discloses a section of the medical delivery system 100 accordingto the first embodiment, and discloses the container 102, the dosingassembly 104 and the rotatable element 106 which is comprises an outerpart 108 and an inner part 110. The rotatable element 106 is retainedaxially relative to the dosing assembly 104 due to engagement betweensnap lock 112 and distal facing surface 114 of the rotatable element106. The inner part 110 defines a first groove part 132 and a secondgroove part 134, in which the projection 126 is positioned in FIG. 3. Asdescribed above, the spring 116 urges the rotational element 106 towardsa first position relative to the dosing assembly 104. FIG. 4 disclosesan exploded view of the medical delivery system 100 according to thefirst embodiment reference numbers identical to the reference numbers ofthe previous figures refer to identical features.

FIG. 5 discloses a second embodiment of the medical delivery system 100.The main difference is the spring 116′ which in the second embodiment alinearly extending spring and not a torsion spring. The advantage of thelinearly extending spring 116′ is that it does not expand radially whenthe rotational element 106 is rotated relative to the dosing assembly104. Instead the spring is bent in the direction indicated by arrow 138.The spring is retained in a passage defined in the housing 140 andextends into a groove 142 defined in the rotatable element 106.

In the embodiments shown, the rotatable element 106 is configured tofully or partly encircle the distal end of the container. Otherembodiments may include a dosing assembly 104 having a rotatable element106 configured to be inserted into a distal opening formed in the distalend face of the container, whereby the mating grooves and projectionsengage internally in said distal opening. In such an embodiment,projections may be formed on an internal wall section of the containerso that the projections exends radially inwards. In this case, amechanism in the dosing assembly may be provided such that a manuallyactuatable member, accessible from the exterior of the dosing assembly,is configured to rotate the rotatable element 106 so as to release thecontainer from the dosing assembly.

In the embodiments shown, the container is rotationally locked relativeto the dosing assembly during insertion and coupling due to theprojections 126 engaging the linear grooves 130 formed in the dosingassembly 104, i.e. the linear grooves 130 defines an axially extendingguide for the projections.

However, any other means may be provided for establishing a rotationallock for rotatively fixing the container relative to the dosing assemblywhen the container is engaged to the dosing assembly. For example, thecontainer may provide a projection formed on an interior proximal wallsection of the container which is configured to engage a correspondingrecessed area formed in the dosing assembly so that the container, whencoupled to the dosing assembly, is rotationally fixed relative to thedosing assembly. In an alternative embodiment, a container having aproximal end face is provided, where the end face is provided withaxially recessed areas that engages corresponding axially exendingprotrusions formed in the dosing assembly.

As shown in the first and second embodiment, the rotational lock mayform an axially extending guide which provides rotationally fixationduring a substantial part of axial movement during coupling anduncoupling of the container to the dosing assembly. However, inalternative embodiments, the rotational lock may provide a rotationallyfixation only during the final stage of axially engaging the containerto the dosing assembly.

1. A container for use in a medical delivery system comprising: acontainer adapted to contain a medicament in a chamber defined by thecontainer and a slidably arranged piston which is moveable in a distaldirection towards an outlet so as to reduce a volume of the chamber andexpel the medicament through the outlet; a dosing assembly, whenpresent, adapted to be fastened to the container, so as to allow adriver of the dosing assembly to move the slidably arranged piston ofthe container in the distal direction; wherein one of the dosingassembly and the container defines a first part comprising a fixed partand a rotatable element rotatably mounted relative to the fixed part,the rotatable element defining at least one projection and/or groovewhich during fastening of the container to the dosing assembly isadapted to be received in/by at least one corresponding groove and/orprojection of a second part which is defined by the other one of thedosing assembly and the container, so as to fasten the container to thedosing assembly; and wherein during fastening of the container to thedosing assembly the rotatable element is adapted to rotate about alongitudinal axis of and relative to said fixed part, and wherein saidfixed part and the second part comprise engaging surfaces configured forrotationally locking said fixed part relative to the second part so thatduring fastening the second part and the fixed part do not rotaterelative to one another.
 2. A container for use in a medical deliverysystem according to claim 1, the container defining said first part andcomprising a rotatable element adapted to rotate about a longitudinalaxis of and relative to the container, the rotatable element defining atleast one projection and/or groove.
 3. A container for use in a medicaldelivery system according to claim 2, wherein the at least oneprojection and/or groove of the rotatable element is adapted to receivea corresponding groove and/or projection of a dosing assembly, so as tofasten the container to the dosing assembly.
 4. A medical deliverysystem comprising: a container adapted to contain a medicament in achamber defined by the container and a slidably arranged piston which ismoveable in a distal direction towards an outlet so as to reduce thevolume of the chamber and expel the medicament through the outlet; adosing assembly adapted to be fastened to the container, so as to allowa driver of the dosing assembly to move the piston of the container inthe distal direction; wherein one of the dosing assembly and thecontainer defines a first part having at least one projection and/orgroove which during fastening of the container to the dosing assembly isadapted to be received in/by at least one corresponding groove and/orprojection of a second part which is defined by the other one of thedosing assembly and the container, so as to fasten the container to thedosing assembly; and wherein the first part comprises a fixed part and arotatable element rotatably mounted relative to the fixed part, therotatable element defining at least one of said projection and/or groovewhich during fastening of the container to the dosing assembly isadapted to be received in/by at least one of said corresponding grooveand/or projection of said second part, and wherein the rotatable elementis adapted to rotate about a longitudinal axis of and relative to saidfixed part during fastening of the container to the dosing assembly andwherein said fixed part and the second part comprises engaging surfacesconfigured for rotationally locking said fixed part to the second partin that the fixed part and the second part each comprises across-section preventing relative rotation, wherein the medical deliverysystem further comprises a housing structure adapted to be gripped by auser and the fixed part comprises the housing structure.
 5. A medicaldelivery system comprising: a container adapted to contain a medicamentin a chamber defined by the container and a slidably arranged pistonwhich is moveable in a distal direction towards an outlet so as toreduce the volume of the chamber and expel the medicament through theoutlet; a dosing assembly adapted to be fastened to the container, so asto allow a driver of the dosing assembly to move the piston of thecontainer in the distal direction; wherein one of the dosing assemblyand the container defines a first part comprising a fixed part and arotatable element rotatably mounted relative to the fixed part, therotatable element defining at least one projection and/or groove whichduring fastening of the container to the dosing assembly is adapted tobe received in/by at least one corresponding groove and/or projection ofa second part which is defined by the other one of the dosing assemblyand the container, so as to fasten the container to the dosing assembly;and wherein the rotatable element is adapted to rotate about alongitudinal axis of and relative to said fixed part during fastening ofthe container to the dosing assembly and wherein said fixed part and thesecond part comprises engaging surfaces configured for rotationallylocking said fixed part relative to the second part during fastening,wherein the medical delivery system further comprises a housingstructure adapted to be gripped by a user and the fixed part comprisesthe housing structure.
 6. A medical delivery system comprising: acontainer adapted to contain a medicament in a chamber defined by thecontainer and a slidably arranged piston which is moveable in a distaldirection towards an outlet so as to reduce the volume of the chamberand expel the medicament through the outlet; a dosing assembly adaptedto be fastened to the container, so as to allow a driver of the dosingassembly to move the piston of the container in the distal direction;wherein one of the dosing assembly and the container defines a firstpart having at least one projection and/or groove which during fasteningof the container to the dosing assembly is adapted to be received in/byat least one corresponding groove and/or projection of a second partwhich is defined by the other one of the dosing assembly and thecontainer, so as to fasten the container to the dosing assembly; andwherein the first part comprises a fixed part and a rotatable elementrotatably mounted relative to the fixed part, the rotatable elementdefining said at least one projection and/or groove which duringfastening of the container to the dosing assembly is adapted to bereceived in/by said at least one corresponding groove and/or projectionof said second part, and wherein the rotatable element is adapted torotate about a longitudinal axis of and relative to said fixed partduring fastening of the container to the dosing assembly and whereinsaid fixed part and the second part comprises engaging surfacesconfigured for rotationally locking said fixed part relative to thesecond part so that the container is fastenable to the dosing assemblythrough a pure translational movement, wherein the rotatable elementencircles at least part of the dosing assembly.
 7. A medical deliverysystem comprising: a container adapted to contain a medicament in achamber defined by the container and a slidably arranged piston which ismoveable in a distal direction towards an outlet so as to reduce thevolume of the chamber and expel the medicament through the outlet; adosing assembly adapted to be fastened to the container, so as to allowa driver of the dosing assembly to move the piston of the container inthe distal direction; wherein the dosing assembly defines a first parthaving at least one groove which during fastening of the container tothe dosing assembly is adapted to be received by at least onecorresponding projection of a second part which is defined by thecontainer, so as to fasten the container to the dosing assembly; andwherein the first part comprises a fixed part and a rotatable elementrotatably mounted relative to the fixed part, the rotatable elementdefining said at least one groove which during fastening of thecontainer to the dosing assembly is adapted to be received by said atleast one corresponding projection of said second part, and wherein therotatable element is adapted to rotate about a longitudinal axis of andrelative to said fixed part during fastening of the container to thedosing assembly and wherein said fixed part and the second partcomprises engaging surfaces configured for rotationally locking saidfixed part to the relative to the second part, wherein said dosingassembly defines at least one linear groove which the at least onecorresponding projection additionally engages during insertion of thecontainer into the dosing assembly, whereby the container isrotationally fixed relative to the dosing assembly.
 8. A medicaldelivery system according to claim 4, wherein during fastening of thecontainer to the dosing assembly, the at least one projection and/orgroove of the rotatable element engages the at least one groove and/orprojection of the second part such that the container is locked fortranslational movement relative to the dosing assembly.
 9. A medicaldelivery system according to claim 4, wherein advancement of the atleast one projection into the corresponding groove during fastening ofthe container to the dosing assembly, causes the rotatable element torotate about the axis of and relative to the container and/or the dosingassembly.
 10. A medical delivery system according to claim 4, whereinthe rotatable element during fastening, is adapted to be rotated lessthan one revolution relative to the fixed part.
 11. A medical deliverysystem according to claim 4, wherein at least one groove of the firstand/or second part is/are shaped such that advancement of thecorresponding projection into the groove during fastening of thecontainer to the dosing assembly, causes the rotatable element to rotatein a first direction and subsequently in an opposite second directionrelative to the first and/or second part.
 12. A medical delivery systemaccording to claim 11, wherein the rotatable element is adapted to berotated between a first position and a second position relative to thecontainer and/or the dosing assembly and wherein the rotatable elementis biased towards the first position.
 13. A medical delivery systemaccording to claim 12, wherein the at least one groove of the firstand/or second part defines a first and a second groove part, and whereinadvancement of a corresponding projection into said groove parts causesthe rotatable element to rotate in the first direction when theprojection, during fastening, is advanced in the first groove part andin the second direction when the projection, during fastening, isadvanced in the second groove part.
 14. A medical delivery systemaccording to claim 13, wherein advancement of the at least oneprojection in the first groove part during fastening of the container tothe dosing assembly causes the rotatable element to be rotated away fromthe first position and wherein advancement of a projection in the secondgroove part during fastening of the container to the dosing assembly,causes the rotatable element to be rotated back towards the firstposition.
 15. A medical delivery system according to claim 13, whereinthe second groove part is steeper than the first groove part relative tothe axial direction of the medical delivery system.
 16. A medicaldelivery system according to claim 13, wherein a plane extending in ageneral direction of the second groove part defines an angle relative tothe axial direction of the medical delivery system which is above 70degrees.
 17. A medical delivery system according to claim 4, wherein theat least one projection and/or the groove define predetermined codinggeometries preventing the container from being fastened to the dosingassembly unless each of the grooves and the projections define apredetermined coding geometry which is selected from a predeterminedgroup of coding geometries.
 18. A medical delivery system according toclaim 17, wherein the coding geometry of the at least one groove and/orprojection is defined by at least one of: a circumferential extent ofthe groove and/or the projection, an axial extent of the groove and/orthe projection, a radial extent of the groove and/or the projection andthe circumferential position of the groove and/or the projection.